Method and apparatus for inserting coil turns into the slots of a magnetic core

ABSTRACT

Method and apparatus for inserting side turn portions of electrical coils in a coil group into selected axially extending coil receiving slots of a magnetic core and for freely shedding end turn portions of at least some of the turns within at least two coils of a coil group radially toward a generally solid or yoke section of the core as the side turn portions of other turns in the selected coils are moved axially toward an end face of the core. Preferably, the at least two coils include two of the innermost coils in a coil group. The side turn portions of the electrical coils are inserted into the axially extending slots by coil turn feeder blades movably supported relative to the divider blade section. The divider blade section and the turn pushing surfaces of the coil turn feeder blades define the side and bottom, respectively, of a series of turn-receiving gaps which have openings in the free extremity of the divider blade section and in which the electrical coils are carried. Insulator pushers may also be provided for inserting insulators into slots after side turn portions of coils have been placed therein. An actuating assembly includes a driver actuated by a suitable power source and effects continuous axial movement of insulator pushers through first, second and third increments of travel to effect placement of insulators in the slots. The divider blade section and the coil turn feeder blades are conjointly actuated in an axial direction during the second increment of travel. Upon completion of the second increment of travel the divider blade section extends axially through the bore of the magnetic core. At this time, the free extremity of the divider blade section in the vicinity of at least two turn-receiving gaps in which the two innermost coils are carried is spaced closely adjacent to the end face of the core. Preferably, the end face of the core and the divider section surface are within one eighth to one quarter inch of each other. During the third increment of travel, the insulator pushers and the coil turn feeder blades are moved in an axial direction relative to the core and divider blade section. During this increment of travel, as the end turn portions of the two innermost coils in one or more selected coil groups move to the gap openings in the free extremity of the divider blade section, the end turn portions move away from the gap openings and toward the yoke section of the core. The method and apparatus can be used even when insulators are not being inserted.

United States Patent Arnold [54] METHOD AND APPARATU S FOR INSERTINGCOIL TURNS INTO THE SLOTS OF A MAGNETIC CORE [72] Inventor: Richard B.Arnold, Fort Wayne, Ind.

(73] Assignee: General Electrlc Company [22] Filed: Dec.21,1970

[21] Appl.No.: 100,219

Hill ..29/205 Eminger ..29/205 Primary Examiner-John F. CampbellAssistant Examiner-Carl E. Hall Attorney-JohnM. Stoudt, Radford M. Reamsand Ralph E Krisher, Jr.

. [57] ABSTRACT Method and apparatus for inserting side turn portions ofelectrical coils in a coil group into selected axially extending coilreceiving slots of a magnetic core and for freely shedding end 1 June27, 1972 vider blade sectionQThe divider blade section and the turnpushing surfaces of the coil turn feeder blades define the side andbottom, respectively, of a series of turn-receiving gaps which haveopenings in the free extremity of the divider blade section and in whichthe electrical coils are carried; insulator pushers may also be providedfor inserting insulators into slots after side turn portions of coilshave been placed therein.

An actuating assembly includes a driver actuated by a suitable powersource and effects continuous axial movement of insulator pushersthrough first, second and third increments of travel to effect placementof insulators in the slots. The divider blade section and the coil turnfeeder blades are conjointly actuated in an axial direction during thesecond increment of travel, Upon completion of the second increment oftravel the divider blade section extends axially through the bore of themagnetic core. At this time, the free extremity of the divider bladesection in the vicinity of at least two turn-receiving gaps in which thetwo innermost coils are carried is spaced closely adjacent to the endface of the core. Preferably, the end face of the core and the dividersection surface are within one eighth to one quarter inch of each other.During the third increment of travel, the insulator pushers and the coilturn feeder blades are moved in an axial direction relative to the coreand divider blade section. During this increment of travel, as the endturn portions of the two innermost coils in one or more selected coilgroups move to the gap openings in the free extremity of the dividerblade section, the end turn portions move away from the gap openings andtoward the,

yoke section of the core. The method and apparatus can be used even wheninsulators are not being inserted.

9 Claims, 20 Drawing Figures PATENTEDJun 2 1 I972 3.6 72.041

' sum 10F a INVENTORI Richard Bfimold.

Attorney.

PATENTEnJum ma SHEEI 2 [IF 8 INVENTOR Frichar'd Bfirnold,

Attor'n PMENTEDJUNZY I972 sum 5 or 8 54 ffi'char-d B. Arnold,

54 b5 62 55 64 BY Attorne PATENTEDJUHZ? I912 3.672.041

- sum 5 or a INVENTOR. Richard B Arnold,

Attorneg PATENTEUJUHN I972 SHEET 7 OF 8 INVENTOR. Richard B. A rnolAttorney.

METHOD AND APPARATUS FOR INSERTING COIL TURNS INTO THE SLOTS OF'AMAGNETIC CORE I CROSS REFERENCE TO RELATED APPLICATIONS This applicationcontains subject matter related to my copending application Ser. No.875,895 filed Nov. 12, 1969, which in turn is a continuation-in-part ofmy copending application Ser. No. 748,405 filed July 29, 1968 and nowabancloned.

BACKGROUND OF THE INVENTION The present invention relates to an improvedmethod and apparatus for inserting or injecting side turn portions of anelectrical coil in the slots of a magnetic core and for moving end turnsof an electrical coil toward a generally solid section of the core. Moreparticularly, the invention relates to a method and apparatus forinserting in the slots of a core the coil side turn portions of at leastthe two innermost coils in at least one coil group of a stator winding,and moving the end .rrn portions of the coils toward a generally solidsection of the core to permit the economic utilization of windingmaterial in the end turn portions of the coils.

My copending application Ser. No. 875,895 is a related application andrefers to the A. P. Adamson US. Pat. No. 2,432,267 and sets forth manyof the desirable advantages that may be attained when coil-inserting orinjecting apparatus includes parts of a relatively rigid construction.

Many of the disadvantages associated with prior arrangements, asidentified and discussed in my related application for example, aremanifest in damaged winding turns and/or damaged coil-inserting tools.Another disadvantage associated with the use of earlier arrangements isthat the end turn portions of the coils in coil groups are trapped andretained in a stator core bore locale or a region adjacent the bore oran extension of the bore during insertion of the coil side turns inaxially extending slots of the core.

Because of this retention of end turns in a bore region or 10- cale, theend turn portions of the coils have been longer than might otherwise benecessary and the means conductor length of coil turns has been longerthan necessary, particularly when two or more of the innermost coils ina coil group have the side turns thereof arranged in relatively closelyspaced pairs of slots. This type of arrangement most frequently occursin sixpole and four-pole winding applications.

It will be understood that by providing shorter end turns, a shortermean coil turn length per coil can be provided, economies in conductormaterial usage may be realized, and, for a given design, improvedoperating efficiencies may be achieved since reduced end turn conductorlength will also result in reduced total electrical resistance in acoil.

With earlier coil-inserting apparatus, while the side turn portions ofcoils have been positioned within axially extending slots of a core, thecoil-inserting tools have trapped the coil end turns in the locale ofthe bore. Thereafter the coil-inserting tools have been withdrawn fromthe bore of the core, and the coil end turns have been at that timereleased in the bore region of the core. This has required the provisionof coil end turns of sufficient length to permit extension thereof intothe region of confinement. It would be desirable to provide an improvedmethod and apparatus for inserting side turn portions of coils intoaxially extending slots of a core while promoting the economicutilization of conductor material in the end turns of at least two ofthe innermost coils of a coil group.

SUMMARY OF THE INVENTION Accordingly, it is a general object of thepresent invention to provide an improved method and apparatus forinserting side turn portions of a coil into a core having axiallyextending slots that promote the economic utilization of windingmaterial.

It is another general object of the present invention to provide animproved method and apparatus for inserting side turn .portions of coilsinto preselected slots of a slotted structure such as, for instance, astator of a dynamoelectric machine, wherein at least some of theconductor end turns of at least two of the innermost coils of at leastone selected coil group are moved radially away from a first position inthe bore region of a slotted core toward a generally solid section ofthe core.

Another more specific object of the present invention is to provide animproved method and apparatus wherein the end turn portions of at leastthe two innermost coils in at least one selected coil group are movedalong gaps defined by stationary coil group separators to gap openingsin the free extremities of the stationary apparatus and causing the endturn portions to be moved away from the gap opening toward a generallysolid section of a core while side turn portions of the coils are beingmoved axially through an axially extending core slot.

In carrying out the objects of my invention in one form, I have providedan improved method and apparatus for axially moving the side turnportions of at least the two innermost coils of a selected coil groupalong selected slots of a slotted structure, as for example, the slotsof the stator core of a dynarnoelectric machine, while effectingmovement of at least some of the end turn portions of the same twoinnermost coils from an initial position adjacent a coil tum-receivinggap toward a generally solid section of the core. The apparatus alsoincludes, in a preferred form, means for holding and guiding insulatorsthat may be placed under the slots of a slotted core structure as moreparticularly described in my application Ser. No. 875,895.

The apparatus, in a preferred form, includes coil insertion meanscomprising coil turn confining means in the form of divider blades whichmay define the side of coil tum-receiving gaps and coil turn feederblades having tum-feeding surfaces movable relative to the dividerblades. The feeder blade tumfeeding surfaces, for at least the twoinnermost coils in a selected coil group, form free extremities of thefeeder blades. In the extended position of these feeder blades, thetum-feeding surfaces are approximately coextensive with the freeextremity of the divider blade section in which tum-receiving gaps areformed. The insulator pushers, divider blade section, and coil turnfeeder blades are actuated by means in form of an actuating assembly asdescribed in my application Ser. No. 875 ,895

During a first increment of travel, the insulator pushers (when used)are brought into driving engagement with insulators in an insulatorguide means. Then, during a second increment of travel, the dividerbladesection and coil turn feeder blades are conjointly moved a predetermineddistance through the bore of the slotted core. At this time the dividerblade section dwells with the free extremity thereof having formedtherein the gap openings for receiving at least two selected innermostcoils of a coil group, lying in closely spaced relationship with an endface of the slotted core. Then, during a third increment of travel, thecoil turn feeder blades move relative to the divider blade section andfeed the end turns of the coils in the coil groups toward the gapopenings. As the end turn portions of at least the selected innermostcoils are pushed to the gap openings, they are caused to move away fromthe gap openings toward the yoke of the core. During the third incrementof travel, only the coil turn feeder blades and the insulator pushersare driven.

The improved method includes the steps of positioning turns of wire ingaps formed in a substantially solid tumreceiving member, moving thetum-receiving member axially adjacent to a slotted structure until atleast a portion of the free extremity thereof lies approximatelyadjacent to an end face of the slotted structure, thereafter moving theside turns of at least two selected coils axially along the slots whilemoving the ends turns of the selected coils axially along the gaps tothe gap openings in the free extremity of the divider blade section, andcausing the end turns of the selected coils to be moved toward agenerally solid section of the core as they emerge from the gapopenings. After the end turn portions of all of the coils have emergedfrom the gap openings, the feeder blades and divider blade section areretracted to an initial position and the core and coil groups areremoved from the coil turn inserting apparatus.

The subject matter which I regard as my invention is particularlypointed out and distinctly claimed in the concluding portion of thespecification. The invention itself, however, taken with further objectsand advantages thereof, may be best understood by reference to thefollowing description taken in conjunction with the accompanyingdrawings in which like reference numerals have been used to identifylike parts and in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view withparts removed, of the upper portion or head assembly of an insulator andcoil-inserting apparatus for use in placing winding coil groups on astator core for use in a motor having a six-pole winding;

FIG. 2 is an exploded perspective view of feeder blades and parts of thedivider blade section for use with the structure shown in FIG. 1;

FIG. 3 is a top view of the insulator and coil-inserting apparatus shownin FIG. 1 with the removed parts assembled therewith;

FIG. 4 is a plan view of a stator core, showing the arrangement ofwindings thereon in schematic form, with which the invention may bepracticed with particular advantage;

FIG. 5 is the upper portion of a sectional view taken in the directionof the arrows 5-5 in FIG. 3;

FIG. 6 is the bottom portion of the view shown in FIG. 5;

FIG. 7 is an enlarged fragmentary sectional view, with parts removed andparts broken away of the FIG. 1 apparatus, and a fragmentary sectionalview of a stator core with the coil turns shown in their respectivepositions after insulator pushers have been driven through an incrementof travel;

FIG. 8 is an enlarged fragmentary sectional view similar to FIG. 7emphasizing movement of coil end turns during a third increment oftravel;

FIG. 9 is a view similar to FIG. 8 emphasizing the continued movement ofcoil turns during the third increment of travel;

FIG. 10 is a view similar to FIG. 9 emphasizing movement of coil turnsduring a later portion of the third increment of travel;

FIG. 11 is a view similar to FIG. 10 emphasizing the position of thecoil turns at the end of the third increment of travel;

FIG. 12 is an elevational view, with parts broken away, of a section ofa core with winding coils positioned in accordance with the inventionand showing the relative configuration and position of the winding coilson the core;

FIG. 13 is a perspective view of the core and coils shown in FIG. 12;

FIG 14 is a plan view of a portion of the structure shown in FIG. 13;

FIG. 15-20 illustrate, with side by side comparisons, advantages thatmay be attained by practicing the invention; and, more specifically,

FIG. 15 is a plan view of a core section, with parts broken away,representing the location of a selected coil group when the presentinvention is not utilized;

FIG. 16 is a plan view substantially identical to FIG. 14;

FIG. 17 is an elevational view, with parts broken away, of the structureshown in FIG. 15;

FIG. 18 is an elevational view substantially identical to FIG. 12;

FIG. 19 is a representation of a portion of an apparatus that may beused to provide the structure of FIG. 15; and

FIG. 20 is a reproduction of a portion of FIG. 11.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Having more specific referencenow to the drawings and particularly to FIGS. 1 through 6, I haveillustrated therein an insulator and turn inserting apparatus adaptedfor use in placing a six-pole winding on a stator core 31 adapted fortwo speed operation and having a start winding, a four-pole mainwinding, and a six-pole main winding. The start winding 32 and mainwindings 33, 34 have been shown in schematic form in FIG. 4 for purposesof clarity.

In the interest of completeness of description the structure of FIG. 4will be more completely described. The four-pole winding 34 was formedof 0.0508 inch diameter aluminum wire and included a turn distributionof 17, 27 and 30 turns from innermost to outermost coils, respectively,for each of the four poles. The six-pole winding 33 was formed of 0.0427inch diameter copper wire and included six coil groups with an innermostcoil to outermost turn distribution of I6, 16, l3); (l6, l6); (I6, 31,40); (14, 31); (16, 31, 40); (l6, 16). These windings were theninnerconnected for two speed operation as taught in Stout US. Pat. No.3,153,184 which issued Oct. I3, 1964. The start winding 32 is formed ofrelatively fine enameled copper wire, e.g., 0.02 l 3 inch diameter wirewith a turn distribution, in each of four poles, one coil group perpole, with 10, 25, and 40 turns for the innermost to outermost coils,respectively, in each coil group.

The present invention may be more advantageously utilized while placingsix-pole and four-pole windings on a stator core with coil-insertingapparatus including a substantially solid tum-receiving member.Accordingly, the invention will be described in connection with apreferred form of apparatus particularly adapted for placing thesix-pole winding 33 on the stator core 31.

Referring now to FIGS. 1 -3, the apparatus 40 includes a head assemblycomprising a substantially solid central divider blade section 41 andother divider section defining elements 42, 43, 44, 46, 47 which aresecured together with the central divider section 41. Disposed betweenthe divider blade segments are a plurality of coil turn feeder blades48, 49, 51, 52, 53 movable relative to the divider blade section. Toavoid confusion, substantially identical feeder and divider bladesegments have been identified with like reference numerals in thedrawings.

The pusher blades and divider section, when assembled together aresupported for movement within a wedge receiving housing 54 which issupported on suitable mounting structure which has been illustrated asincluding a turntable 56. Keys 57 prevent relative rotation between thefeeder and divider blades and the housing 54 and may also interfit witha stator core to prevent rotation of the core on the apparatus 40 whensupported on the head assembly.

It will be noted from an examination of FIG. 2 that the feeder blades51, 52, 53 are formed with slots 58, $9, 61 which cooperate with stops62, 63, 64 which form part of the divider blade section. These stops62-64 limit movement of the feeder blades relative to the divider bladesection and also impart rigidity to the structure and thus help toprevent binding of the feeder blades in the divider blade section.

As in the case of my application Ser. No. 875,895, the entire disclosureof which is specifically incorporated herein by reference, insulatorsmay initially be loaded into the apparatus 40 by inserting them intoinsulator guide apertures 66 in a wedge guide 65 before a stator ispositioned over the head assembly and before the coils are placed in thetum-receiving gaps of the head assembly. Preferably, the insulators aredirectly loaded from an insulator making an inserting apparatus ofsuitable construction. Further, it will be understood that afler theinsulators are loaded in the guide apertures 66, a predetermined numberof coils are initially developed with a preselected number of turns percoil from insulated wire and disposed in the appropriate tum-receivinggaps of the head assembly. This coil developing operation may beaccomplished in the manner desired, such as, for example, in the waydisclosed in my copending patent application Ser. No. 748,406 which wasfiled on July 29, I968 and is assigned to the assignee of the presentapplication.

The improved insulation and turn inserting apparatus 40 is readilyadapted for use in conjunction with apparatus of the type disclosed inmy copending application Ser. No. 748,406

andthe apparatus 40 is rotatably supported on the table 56 by ballbearings 93. As best shown in FIG. 3, a driving gear 67 meshes with adriven gear 68 attached to the guide housing 54. The driving gear 67 isdriven to effect a desired number of degrees rotation of the apparatus40 in order to align the tumreceiving gaps of the apparatus with a coilwinder or coil transfer device as more specifically described in myapplication Ser. No. 875,895.

The insulator and turn inserting apparatus is generally comprised of anactuating assembly as well as the head assembly. The actuating assemblyis shown and described in my application Ser. No. 875,895 and thereforeis not otherwise illustrated in this application.

Still having reference to FIG. 3, the divider blade section and coilturn feeder blades define tum-receiving gaps in which the turns of thecoils to be inserted are placed. The bottom of these gaps are defined bythe turn pushing surfaces of the feeder blades 51-53, 48 and 49. Theperipheral edges of the gaps form slits 71, which are aligned with theaxially extending slot entrances of a stator core when it is in positionon the head assembly. It will be understood that the insulator guideapertures 66 are also axially aligned with the stator slots so thatinsulators can be pushed therein as the side turn portions of a coil aremoved through the slot entrances.

As in the case of my application Ser. No. 875,895, the leading edges ofinsulators preferably trail behind the turn pushing surfaces of the coilturn feeder blades by a predetermined distance during coil insertion.

It will be noted that the three feeder blades 53 are each formed with areduced portion 72 which define one sidev of the tum-receiving gaps 73in order to eliminate friction between the coils disposed in the gaps 73and the stationary divider blade section walls 74 during movement ofcoil turns along the gap 73.

Now referring to FIGS. 1, 2, 5 and 6, the guide members 62, 63, 64, 76,and 77 are held in assembled relation with the divider blades by screws78 and removable pins 79. These guide members provide accuratelymaintained spaces in which the coil turn feeder blades are slidablydisposed. The divider blade section 41 is attached by means of a stud 81to a shaft 82 which is interconnected with an actuating assembly asabove mentioned for effecting axial movement of the section 41 relativeto the housing 54.

The shaft 82 is provided with a central bore 83 sealed by a set screw84. Secured to the shaft 82 is a cylinder cap 86 threaded into acylinder 87 to which a cap plate 88 secures a feeder blade retainer 89by means of a plurality of bolts 91. In addition, as shown and describedin my application Ser. No. 875,895, a pair of driver guide rods aresecured to the locating plate 92. Then, when the gear 68 is driven, thewedge housing 54 rotates relative to the table 40 in the ball bearings93, and the driver guide rods ensure that the actuating assembly willrotate with the locating plate 92. The feeder blades are secured to thefeeder blade retainer by screws 94 and held in spaced relationship byspacers 96, 97, 98, 99, 101.

During operation of the apparatus 40, a source of air pressure isadmitted to the bore 83 of the shaft 82 and through the radialpassageway 102 in the shafi to the feeder blade cylinder 87. Asdescribed in my application Ser. No. 875,895, compression of air withinthe cylinder 87 cushions the feeder blades 48, 49, 51, 52, 53 as theymove to a fully extracted or extended position relative to the dividerblade section.

In addition, the relative positions of the insulator or wedge pushers103, feeder blades, and divider blade section in the apparatus 40 areall relatively adjustable so that cores having various stack heights maybe accommodated by the apparatus embodying the present invention.

The drawings, FIGS. 7 through 11, illustrate the operation of theapparatus 40 during insertion of one group of coils of the six-pole sixcoil group winding 33 into a stator core 31 having a stack height ofapproximately one and three quarters of an inch and a bore of aboutthree and one half inches. In FIGS. 7 through 1 1, the side turnportions 106 of some of the coils of the four-pole winding 34 have alsobeen shown, since the winding 34 is placed on the stator core 31 priorto placement of the winding 33.

Although the views of FIGS. 7-11 are taken in the direction of thearrows 5-5 in FIG. 3 and through the center of the tooth 107 of thestator core 31, parts of the stator core 31, including one tooth 107have been broken from these FIGURES, for purposes of clarity, so thatthe slot 108, defined by the teeth 107 and 109 will be readily apparent.In addition, the key 57 has been omitted from the keyway 111.

It will be understood that FIGS. 7 and 11 are representative of theextreme limits of travel of the feeder blades 51-53 relative to thedivider blade section during operation of the apparatus 40 with a oneand three quarter inch stack height stator core. With reference to FIG.7, tum-receiving gaps 112 and. 1 13 are defined, at the sides thereof,by the divider blades 44-43 and 43-42 respectively and the coil turnpushing surface of the feeder blades 53, 52 define the bottoms of thesegaps. The sides of the gap 1 14 are defined by the surface of thedivider blade 42 and the surface 72 of the feeder blade 53, whereas thebottom of the gap 114 is defined by the coil turn pushing surface of thefeeder blade 53. Thus, the divider blades 42, 43 act as coil separatorsfor the coils 1 16, l 17, 118.

It should be noted that when the end turn portions of the coils aredisposed in the gaps 112, 113, 114, they tend to be supported at theedges of the feeder blades and bow slightly upwardly because thecurvature of the coils and the weight of the coils tend to bend the bulkof the coils downwardly about the external periphery of the housing 54.A slight space which may occur for this reason between the'centralportion of the feeder blade pushing surfaces and the bottom winding turnof the coils have been has been exaggerated in FIG. 7. One of thesespaces, i.e., the space between the lowermost turn 1 19 in the coil 116and the pushing or feeding surface of the feeder blade 53 has beendenoted by the reference numeral 121.

It will be understood that in one cycle of operation of the apparatus40, six coil groups are inserted into selected slots of the stator core31 for movement by six sets of feeder blades, but that for clarity ofdescription, an operational cycle of the apparatus will now be discussedwith reference to only the coil group containing coils 116, 117, 118 andthe structure shown in FIGS. 7-11.

At the beginning of a cycle, the coils 116, 117, 118 are placed in thetum-receiving gaps 112, 113, 114. In the specific exemplification, thecoils were wound of 0.0427 inch diameter insulated wire with 16 turns incoil 116, 31 turns in coil 117, and 40 turns in coil 1 18.

The core 31 is then placed on the head assembly of the apparatus andclamped in place, with the keys 57 projecting into slot openings of thecore to prevent rotation of the core relative to the head assembly.

With the divider blades, feeder blades, and insulator pushers relativelyadjusted for insertion of coils into a one and three quarter inch stackheight core, the surface of the end face 122 of the core 31 lies closelyadjacent to the plane P in which the free extremities of the dividerblades 44, 43, 42 lie after the core 31 has been clamped in place. Ihave found that a spacing of about one eighth of an inch between the endface 122 of the core 31 and the plane P is a suitable spacingtherebetween.

This spacing is preferably selected so that a core is tightly retainedon the divider blade section with the free extremity of the bladesectionextending through the bore of the core. For cores with stackheights of from one to two and one half inches, a spacing of one eighthinch has been found to be satisfactory for this purpose and is thereforepreferred in order to permit efiicient utilization of conductor materialin the end turn portion of coils injected with apparatus embodying theinvention.

When the apparatus 40 is used to insert windings into cores having stackheights greater than the stack height of the core 31, the apparatus 40is adjusted to accommodate those cores as will be understood byreference to my application Ser. No.

875,895 with longer cores, the cores are clamped in place on the headassembly of the apparatus and the divider blade section is moved axiallythrough the bore of the core so that the free extremity thereof isspaced closely adjacent to the upper end face of the core. It willtherefore be appreciated that, for longer cores as well as the core 31,the free extremity of the divider blade section and the core axiallyrelatively movable.

At the most extended position of the feeder blades relative to thedivider blades (as shown in FIG. 11), the feeder blade turn pushingsurfaces are also closely adjacent to the end face of the core. For thestructure shown in FIG. 11, the pusher blade surfaces project only aboutone sixteenth of an inch above the plane P.

Now referring again to FIG. 7, it will be understood that the statorcore 31 and divider blades are initially positioned relative to eachother as shown. Then the feeder blades 51, 52, 53 are advanced in onecontinuous motion relative to the divider blades to the relativeposition illustrated in FIG. 11. FIGS. 8, 9 and 10 approximatelyrepresent movement of the coils 116, 117, 118 relative to the core 31during operation of the apparatus. Although the actual amount of bendingof the turns within a coil vary, and the precise mechanism by which thecoil turns are bent during the insertion cycle is not known withcertainty, visual inspection of stators after coil insertion with theapparatus 40 reveal small bends in the coils which correspond, forexample, to bends 125, 126 in FIG. 8. Accordingly, the forces applied tothe coils 116, 117, 118 during insertion and the resultant affect on thecoils will also be described as best comprehended at this time.

Upon commencement of operation of the apparatus 40, the end turns of thecoils 116, 117, 1 18 of the coil group move axially through the bore ofthe core toward the openings in the free extremity of the divider bladesection. Then, as the side turns of the coils engage the closed end ofthe winding slots in the core (or the side turns 106 of windingspreviously placed in the slots), the coil turns 116, 117, 118 areapparently deformed and slightly bent as at 125, 126 while the sideturns of the coils 116, 117, 118 move axially through the axiallyextending passageways of the core 31, i.e., the winding receiving slots.

In FIG. 8, the deformation of turns in the coil 116 denoted at 125 and126 is believed to be a result of the interaction of the corners 127,128 of the feeder blade 51 and the winding 106 with the coil 116.

FIG. 8 also illustrates the movement of the turns 129, 131 of the coil118 from the opening of the gap 114. It will be noted that as the turnsof the coil 118 emerge from the opening of the gap 114, they are freelyshed from the apparatus 40, and are caused to move toward the generallysolid section of the core 31. With continued movement of the feederblades 51, 52, 53, the end turns 129, 131 and other turns emerging fromthe gap openings are also move outwardly from the center of the boreofthe core 31.

This movement of the coil end turns is also shown in FIG. 9 and isbelieved to be caused at least in part by the frictional engagement ofthe side turn portions of other turns 132, 133 with the side turnportions of the turns 129, 131 within the tum-receiving slots of thecore. Thus it is believed at this time that the turns 129, 131 aretrapped by other turns and moved by the other turns of the coil 1 18.Furthermore, the blades 51, 52, S3 and coil turns move relativelyrapidly and movement of the coil end turns away from the gap openingsmay also be caused, in part, by the inertia of the coil end turns aswell as by some spring action of the wire turns which is believed tooccur because of deformation of the turns during winding and insertionand tendency of the turns to return to an undeformed configuration.

FIG. 10 further illustrates the movement of the end turns of the coils116, 117, 118 as the end turns 135, 136 of the innermost coil 116 in thecoil group are shed from the apparatus 40. This view also clearlyreveals the movement of the wedge 138 along the opening of the slot 108.At the end of feeder blade movement, the feeder blades 51, 52, 53 mayproject slightly beyond the extremity of the divider blade section, andthe end turns of each of the coils will have moved toward the generallysolid section of the core 31. However, as shown in FIG. 11, some turnsof the coils may continue to be in engagement with the edges or comersof the feeder blades.

Thus, during insertion of the coils of winding 33, the end turns of thecoils are moved axially through the bore of the stator 31 as the sideturns thereof are advanced axially along the axially extendingpassageways or slots of the core. Then, for each coil within each coilgroup, the end turn portions of the turns in the coil are shed from theapparatus 40 and caused to move toward the yoke section 137 of the core.As previously discussed, as the end turns emerge from the gap openingsthe end turns move toward the yoke section of the core. In fact, whenobserving the apparatus 40 in operation, the end turns of the coilsalmost seem to pop from the gap openings and move to the position shownin FIG. 11. The feeder blades move from the first position shown in FIG.7 to the second position shown in FIG. 11 rather rapidly, e.g., thefeeder blades travel about four to seven inches in about one to twoseconds. When observing the rapid movement of the coil end turns awayfrom the gap openings, a rapid, continuous fan-like movement appears totake place. After all of the end turns of the coils have snapped orotherwise emerged from the gap openings formed in the free extremity ofthe divider blade section and have moved from a first position in thebore region or locale of the core to a second position closer to theyoke of the bore, the feeder blades and divider blade section areretracted as a unit through the bore of the core to the relativepositions shown in FIG. 7. Then the core 31 with winding 33 in place isremoved from the apparatus 40.

In the specific exemplification represented by FIGS. 7 through 11, thecoil 116 is the innermost coil, the coil 118 is the outermost coil, andthe coil 117 is an intermediate coil of one of one coil group. Formaximum advantage, it is preferred that the end turns of all three coils116, 117, 118 be freely shed as they emerge from the gaps in the freeextremities of the divider blade section. However, benefits of theinvention will still be realized if the end turns of the two innermostcoils 116 and 117 are freely shed from the apparatus as they emerge fromthe gaps 112, 113. In the case of the coil groups moved by the feederblades 48, 49, wherein there are only two coils in a coil group, the twoinnermost coils would both be innermost coils, although one of themcould also be defined as an outermost coil for that coil group.

Turning now to FIGS. 12 through 14, the final relationships of theinsulators or wedges 138 and coil groups in the stator core 31 areillustrated. In this view, windings forming part of the second mainwinding 34 have been broken away for purposes of clarity.

FIG. 14 has been reproduced as FIG. 16 and a portion of FIG. 12 has beenreproduced as FIG. 18. A portion of FIG. 11 has been reproduced as FIG.20. For purposes of comparison, FIG. 19 shows an apparatus 139 whereinthe outermost and next to innermost coils 141, 142 in a coil group havebeen trapped and retained by a coil feeder blade 143. The apparatus 139does not embody the present invention and coils 141, 142, 144 injectedby the apparatus 139 in a core 146 would appear as shown in FIGS. 15 and17.

Comparing first FIGS. 19 and 20, it will be appreciated that with theapparatus 139, a sufficient length of winding material must be providedfor each end turn of the coils 141, 142 to extend from the core end face147 upwardly and radially inwardly to the confined bore region or locale148 and back to the end face 147 of the core 146. Not only must asufficient length of conductor be provided to pennit retention of thecoil end turns within the confined bore region 148 but, furthermore,sufficient turn length must also be provided to permit a stacking of thecoil end turns between the feeder blades 143, 149. The amount ofconductor material required for this purpose will be best appreciated bycomparing FIGS. 15, 17, with FIGS. 16, 18.

The increased use of conductor material (which may be any suitablematerial, e. g., copper or aluminum) for the formation of winding endturns when they are to be injected with the apparatus 139 is furtheraggravated by the fact that with automatic winding equipment, all of thecoil turns in a given coil are formed of the same length of conductor.This means that the extra conductor length provided for the end turn 151must also be provided for all other end turns within the same coil.Thus, as will be quickly appreciated from a comparison of FIGS. and 16,and FIGS. 17 and 18, the mean arcuate height and mean arcuate length ofthe end turns of the coils 141, 142 could be reduced by following theteachings of the present invention.

Although in the illustrated embodiments of my invention, 1 have shownthe coil receiving gaps of the apparatus 40 as being substantiallyconstant, it will be appreciated that in some applications it may bedesirable to vary the dimensions of the gaps. From the foregoingdescription of the improved insulator and turn inserting apparatus andmethod exemplifying my invention, it will be apparent that the placementof insulators and coil turns into a slotted structure can be efficientlyaccomplished while significantly reducing the amount of winding materialthat must be provided for the end turn portions of the winding. Thisprovides the advantages in a finished motor of reducing the cost thereofas a result of reduced material usage; improving the efficiency for agiven motor design by reducing the winding resistance thereof; reducingthe amount of heat associated with a given power input and given motordesign because of lower winding resistance; and reducing the physicalbulk in the end turn region.

Furthermore, with the improved head assembly arrangement herein shown, arigid structure is provided for precisely controlling the insertion ofcoil side turn portions of a winding.

While I have shown and described various embodiments of the invention,it will be obvious to those skilled in the art that changes andmodifications may be made therein without departing from the invention.It is therefore intended in the appended claims to cover all suchchanges and modifications that fall within the true spirit and scope ofmy invention.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. A method of inserting side turn portions of a group of at least twoelecfiical coils formed of conductor wire into predetermined axiallyextending slots of a core having a generally solid section and axiallyextending slot entrances in communication with a periphery of the coreand extending between two faces of the core, the method comprising thesteps of moving side turn portions of the electrical coils into andaxially along the axially extending slots while confining end turnportions of the electrical coils in a locale away from the slotentrances and generally solid section; releasing at least some of theend turn portions of at least the two innermost coils of a coil groupfor movement toward the generally solid section of the core; and causingsaid at least some the end turn portions to be displaced generallytoward the generally solid section while advancing side turn portions ofthe electrical coils connected to other end turn portions axially alongthe axially extending slots.

2. The method of claim 1 including moving other end turn portions of theat least two coil groups to the end of a path of confinement in thelocale away from the slot entrances and generally solid section of thecore; and causing the other end turn portions of the at least two coilgroups to be displaced generally toward the generally solid section ofthe core.

3. A method of inserting side turn portions of a group of electricalcoils formed of conductor wire into predetermined axially extendingslots of a core having a yoke section and axially extending slotentrances in communication with a periphery of the core and extendingbetween two end faces of the core while moving at least some of the endturns of at least two coils of a given coil group from a region ofconfinement toward the yoke section; the steps of: confining the endturn portions of the coils in tum-receiving gaps extending to the freeextremity of an inserting apparatus and having movable blades disposedtherein; axially inserting some of the side turn portions of at leasttwo coils in a given coil group into the predetermined slots by movingthe movable blades within the gaps; transporting at least some of theend turn portions of at least two coils along the gaps to the freeextremity of the apparatus; releasing at least some of the end turnportions of the at least two coils from confinement in the gaps formovement toward the yoke section; thereby moving at least some of theend turn portions toward the yoke section while continuing to move themovable blades within the gaps.

4. The method of claim 3 including transporting other of the end turnportions of the at least two coils along the gaps to the free extremityof the apparatus and causing the other of the end turn portions of theat least two coils to move away from the tum-receiving gaps and towardthe yoke section.

5. Apparatus for inserting coil side turn portions of a group ofelectrical coils formed of conductor wire into predetermined axiallyextending slots of a core having a yoke section, a central axiallyextending bore, and axially extending slot entrances in communicationwith the bore and the slots, while moving the end turn portions of atleast two coils of a given coil group toward the yoke section, saidapparatus comprising: a divider blade section and coil turn feederblades having free extremities for extension along the bore of the core;adjacent ones of a plurality of the divider blades defining gaps inalignment' with predetermined ones of the slot entrances of the core;said feeder blades being mounted within the gaps for movement betweenfirst and second positions with the free extremities of a plurality ofthe feeder blades being spaced from the divider blade free extremitiesand forming the bottom of the gaps in the first position; said freeextremities lying closely adjacent to the divider blade free extremitiesin the second position; and means for moving the feeder blades betweenthe first and second positions whereby winding end turns are moved tothe divider blade free extremities by feeder blades and freely shedtoward the yoke section of the core.

6. The apparatus of claim 5 wherein the coil turn feeder blades anddivider blade section are relatively positioned for moving at least fourcoil groups and the free extremities of at least two adjacent feederblades, adapted to move the two innermost coils of a coil group, lieclosely adjacent to the free extremity of the free extremity of thedivider blade section in said second position.

7. Apparatus for inserting coil side turn portions of a group ofelectrical coils formed of conductor wire into predetermined axiallyextending slots of a core of preselected axial length and having acentral axially extending bore and axially extending slot entrances incommunication with the bore, the apparatus comprising: a plurality ofspaced apart divider blades arranged to define means for receiving thecoil turns of a group of coils and having free extremities for passagethrough the bore of a core; a plurality of coil turn feeder bladespositioned between said divider blades; said feeder blades being formedwith tum-pushing surfaces; the tumpushing surfaces of the feeder bladesin a first position forming the bottom of tum-receiving gaps formedbetween adjacent divider blades; said divider blades and said feederblades being received in the bore of the core with said gaps inalignment with predetermined ones of the axially extending slotentrances; the tum-pushing surface of a first feeder blade being adaptedfor pushing an innermost coil of a coil group and the tum-pushingsurface of a second feeder blade being adapted for pushing a next toinnermost coil of the coil group; said divider blades and said feederblades being mounted for relative movement in an axial direction toinsert the side turn portions of the group of coils into the slots ofthe core with at least the first and second feeder blades being limitedin movement relative to the divider blades, whereby the free extremityof the first and second feeder blades are movable between the firstposition and a second position adjacent to the free extremity of thedivider blade section; and means for moving the feeder blades betweenthe first and second positions for moving the 9. The apparatus of claim8 wherein at least one of the feeder blades includes an extension thatforms one side of a tum-receiving gap in the apparatus; said extensionprojecting substantially beyond the free extremity of the divider bladesection when the feeder blades are in the second position.

1. A method of inserting side turn portions of a group of at least twoelectrical coils formed of conductor wire into predetermined axiallyextending slots of a core having a generally solid section and axiallyextending slot entrances in communication with a periphery of the coreand extending between two faces of the core, the method comprising thesteps of moving side turn portions of the electrical coils into andaxially along the axially extending slots while confining end turnportions of the electrical coils in a locale away from the slotentrances and generally solid section; releasing at least some of theend turn portions of at least the two innermost coils of a coil groupfor movement toward the generally solid section of the core; and causingsaid at least somE the end turn portions to be displaced generallytoward the generally solid section while advancing side turn portions ofthe electrical coils connected to other end turn portions axially alongthe axially extending slots.
 2. The method of claim 1 including movingother end turn portions of the at least two coil groups to the end of apath of confinement in the locale away from the slot entrances andgenerally solid section of the core; and causing the other end turnportions of the at least two coil groups to be displaced generallytoward the generally solid section of the core.
 3. A method of insertingside turn portions of a group of electrical coils formed of conductorwire into predetermined axially extending slots of a core having a yokesection and axially extending slot entrances in communication with aperiphery of the core and extending between two end faces of the corewhile moving at least some of the end turns of at least two coils of agiven coil group from a region of confinement toward the yoke section;the steps of: confining the end turn portions of the coils inturn-receiving gaps extending to the free extremity of an insertingapparatus and having movable blades disposed therein; axially insertingsome of the side turn portions of at least two coils in a given coilgroup into the predetermined slots by moving the movable blades withinthe gaps; transporting at least some of the end turn portions of atleast two coils along the gaps to the free extremity of the apparatus;releasing at least some of the end turn portions of the at least twocoils from confinement in the gaps for movement toward the yoke section;thereby moving at least some of the end turn portions toward the yokesection while continuing to move the movable blades within the gaps. 4.The method of claim 3 including transporting other of the end turnportions of the at least two coils along the gaps to the free extremityof the apparatus and causing the other of the end turn portions of theat least two coils to move away from the turn-receiving gaps and towardthe yoke section.
 5. Apparatus for inserting coil side turn portions ofa group of electrical coils formed of conductor wire into predeterminedaxially extending slots of a core having a yoke section, a centralaxially extending bore, and axially extending slot entrances incommunication with the bore and the slots, while moving the end turnportions of at least two coils of a given coil group toward the yokesection, said apparatus comprising: a divider blade section and coilturn feeder blades having free extremities for extension along the boreof the core; adjacent ones of a plurality of the divider blades defininggaps in alignment with predetermined ones of the slot entrances of thecore; said feeder blades being mounted within the gaps for movementbetween first and second positions with the free extremities of aplurality of the feeder blades being spaced from the divider blade freeextremities and forming the bottom of the gaps in the first position;said free extremities lying closely adjacent to the divider blade freeextremities in the second position; and means for moving the feederblades between the first and second positions whereby winding end turnsare moved to the divider blade free extremities by feeder blades andfreely shed toward the yoke section of the core.
 6. The apparatus ofclaim 5 wherein the coil turn feeder blades and divider blade sectionare relatively positioned for moving at least four coil groups and thefree extremities of at least two adjacent feeder blades, adapted to movethe two innermost coils of a coil group, lie closely adjacent to thefree extremity of the free extremity of the divider blade section insaid second position.
 7. Apparatus for inserting coil side turn portionsof a group of electrical coils formed of conductor wire intopredetermined axially extending slots of a core of preselected axiallength and having a central axially extending bore and axially extendingslot entrances in communication with the bore, the apparatus comprising:a plurality of spaced apart divider blades arranged to define means forreceiving the coil turns of a group of coils and having free extremitiesfor passage through the bore of a core; a plurality of coil turn feederblades positioned between said divider blades; said feeder blades beingformed with turn-pushing surfaces; the turn-pushing surfaces of thefeeder blades in a first position forming the bottom of turn-receivinggaps formed between adjacent divider blades; said divider blades andsaid feeder blades being received in the bore of the core with said gapsin alignment with predetermined ones of the axially extending slotentrances; the turn-pushing surface of a first feeder blade beingadapted for pushing an innermost coil of a coil group and theturn-pushing surface of a second feeder blade being adapted for pushinga next to innermost coil of the coil group; said divider blades and saidfeeder blades being mounted for relative movement in an axial directionto insert the side turn portions of the group of coils into the slots ofthe core with at least the first and second feeder blades being limitedin movement relative to the divider blades, whereby the free extremityof the first and second feeder blades are movable between the firstposition and a second position adjacent to the free extremity of thedivider blade section; and means for moving the feeder blades betweenthe first and second positions for moving the end turns of coils alongthe gaps and shedding the end turns from the gaps.
 8. The apparatus ofclaim 7 wherein the divider blade section and turn feeder blades form asubstantially solid and rigid assembly, and the feeder blades arearranged for effecting the movement of coils of at least four coilgroups.
 9. The apparatus of claim 8 wherein at least one of the feederblades includes an extension that forms one side of a turn-receiving gapin the apparatus; said extension projecting substantially beyond thefree extremity of the divider blade section when the feeder blades arein the second position.